First-party data is information that an organization collects directly from its own audience — website visitors, customers, or subscribers — through interactions those users have with the organization's own properties, and with their explicit consent.
The term "first-party" distinguishes this data by its source. When a user fills out a sign-up form, makes a purchase, clicks through a newsletter, or accepts a site's cookie policy, the organization receives data straight from that individual. No intermediary is involved. This stands in contrast to third-party data, which is aggregated and sold by external brokers who have no direct relationship with the end user, and to second-party data, which is first-party data shared or sold by a trusted partner organization.
First-party data typically includes behavioral signals such as pages visited, products browsed, and time spent on site, as well as declared attributes like name, email address, location, and purchase history. A closely related concept is zero-party data, which refers specifically to information a user proactively and intentionally shares — such as preferences submitted through a quiz or a preference center. While zero-party data is a subset of the broader first-party category in practice, some practitioners treat it as a distinct tier because of its higher degree of intentionality and transparency.
Why First-party Data Is Growing in Importance
For much of the web's history, marketers and advertisers relied heavily on third-party cookies to track users across sites and build detailed behavioral profiles. That model is in decline. Browsers including Safari and Firefox have blocked third-party cookies by default for years, and regulatory frameworks such as GDPR and CCPA have imposed strict requirements around user consent and data collection. This broader shift toward a cookieless environment has made first-party data the most reliable and legally sound foundation for audience targeting, personalization, and measurement.
Because first-party data is collected with the user's knowledge and consent — often facilitated through a cookie consent mechanism or a formal privacy notice — it carries fewer compliance risks than data sourced externally. Organizations that invest in building robust first-party data strategies, such as loyalty programs, gated content, and preference centers, are better positioned to maintain effective marketing as third-party tracking erodes.
How It Is Used
First-party data powers a wide range of applications: personalizing on-site experiences, segmenting email audiences, informing product recommendations, and feeding machine learning models used for ad targeting. It also serves as the input for cookieless tracking approaches such as server-side analytics and data clean rooms, where user-level insights can be activated without relying on browser-based identifiers. Because the data originates from a direct relationship, it tends to be more accurate, more current, and more actionable than data acquired through third parties.